1. Field of the Invention
Embodiments of the present invention relate generally to mobile terminal technology and, more particularly, relate to a method, apparatus, and computer program product for selecting a method of providing location information associated with a mobile terminal.
2. Background of the Invention
In cellular networks like GSM, WCDMA etc., it is typically possible to determine the geographic location of the mobile terminals, and provide location-based or location-aware services based upon the location of the mobile terminals. Location-based services are those in which the location information of the mobile terminal is a fundamental enabler for offering the services. Examples of these are fleet management/tracking, find-a-friend services, location based games, and navigation services. Location-aware services are services in which available location information of the mobile terminal will enhance the usability of existing services, making them more attractive and easy to use. The location information is not a fundamental enabler for offering these kinds of services. Examples of this category are location based weather forecasts, restaurant finders, and city guides.
In various applications, service announcements can be transmitted to mobile terminals on the basis of a service request of a subscriber in a mobile communication system. Generally, the provision of these chargeable services is most often arranged from outside the actual mobile communication system. By making a call to a required service number or sending a request over the Internet, for example, a mobile subscriber is able to order a selected service announcement to be delivered to the mobile terminal, such as via the display of the mobile terminal. Of these individual services, e.g., weather forecast, traffic announcements, local news and other local services, such as taxi ordering, service station announcements and so on, are services where the mobile subscriber selects the desired announcement on the basis of the geographic area. The mobile subscriber generally wishes to have the service announcement related to his/her current location which varies because of the mobile nature of the mobile subscriber.
Numerous means of obtaining information about a current location of a mobile terminal are becoming more widely available for use on mobile terminals. Examples of such means include cell identity location (cell ID), Uplink Time Difference Of Arrival (U-TDOA), Global Positioning System (GPS), Assisted-GPS, etc. However, each means of obtaining location information has a different level of accuracy. For example, Assisted-GPS is currently able to offer location accuracy of about 10 m to 100 m. Meanwhile, cell ID is typically accurate to within only about 200 m to several kilometers. Furthermore, cell ID accuracy may vary significantly between different cells. Each of the different means of obtaining location information also uses a corresponding different amount of resources to obtain location information. For example, computing capacity of a location server, communication bandwidth and time consumption are all resources which are utilized at varying degrees by each of the means of obtaining location information.
Currently, a location server network element (such as a secure user plane location platform (SLP) with an open mobile alliance (OMA) standardized Secure User Plane Location (SUPL) framework, or a Serving Mobile Location Center (SMLC) with 3GPP standardized location solution for GSM/WCDMA) determines which method to use for obtaining location information in response to a location request based on accuracy and response time requirements included in the location request. However, this may result in an iterative process that consumes relatively large amounts of the location server's resources. More specifically, if a location request specifies a quality of service (QoS) requirement for accuracy, the location server will obtain location information using a first method that typically consumes least resources. If the first method produces location information that fails to meet accuracy requirements, then a second method will be used to obtain location information. Typically this second method is expected to provide better location accuracy, but it usually also consumes more resources. This process may continue until the QoS requirement is met, thereby consuming large amounts of resources of the location server. Accordingly, there is a need for a means by which a method for providing location information may be selected which minimizes or at least reduces the consumption of location server resources, but which still guarantees that the requested location accuracy can be met.